Tagging resources is highly coupled to the team culture, organizational tree, etc.
Each resource can have a maximum of 15 tags
The tag name is limited to 512 characters, and the tag value is limited to 256 characters
Tag resources when creating them, this will prevent un-tagged resources somehow (glitch on provisioning steps of creating resources, etc.)
Use tags to group/filter resources for cost analysis
CostCenter=CC1234
BillingCode=BC1234
Region=Global or Region=LATAM
Responsible=DataScienceTeam-15 or Owner=john@doe.com
Use tags to group/filter resources for versioning
Version=1
Version=2019-08-16
Use tags to group/filter resources for projects
Project=AnalyticalSandboxes or Project=Project1234
Use tags to group/filter resources for use-cases
Environment=Staging
Reason=FrontEnd
Dependency=WebApi
Naming conventions for Azure resources
Tagging Best Practices for Cloud Governance and Cost Management
Azure Resource Tagging Best Practices